【作者】 王伟；

【导师】 高天翔； 尤锋；

【作者基本信息】 中国海洋大学 ， 渔业资源， 2005， 硕士

【摘要】 本文以微卫星遗传标记(microsatellite DNA)为手段,对山东近海自然和养殖牙鲆Paralichthys olivaceus(T. & S.)进行了群体遗传学研究,以此为基础对人工诱导的牙鲆异质雌核发育群体的遗传变异及基因着丝点之间的重组率进行了分析。另外,通过对人工诱导的雌核发育异质和同质群体的研究构建了微卫星标记一着丝点连锁图谱,并分析了微卫星标记之间的连锁关系。主要结果如下: 1、首先建立了适于牙鲆微卫星分析的方法,研究了山东近海牙鲆自然群体和一个养殖群体在10个微卫星基因座位上的遗传多样性(Po1,Po13,Po33,Po35,Po42,Po48,Po56,Po89,Po91,Po-strl),10个座位均为多态; 它们的等位基因平均数(a)分别是6.7和6.1,每个基因座位有效等位基因数(α_e)分别为1.8～6.8和2.5～6.7,群体平均杂合度(H)分别为0.8120和0.7310;两个群体间的遗传相似性系数、遗传距离和基因分化系数为0.8558、0.1557和0.0558;自然群体内每个座位上的多态信息含量(PIC)为0.59～0.84、个体识别率(DP)为0.54～0.86、非父排除率(PPE)为0.41～0.72,其累积个体识别率和非父排除率均达到0.9999,表明所选座位属中高识别力的遗传标记,可以将它们应用于今后牙鲆雌核发育群体的遗传变异分析以及进一步的遗传育种的研究中。 2、在人工异质雌核发育群体中,对经筛选所获得的10个基因座进行分析,Po91可能因为出现了无效等位基因而没有扩增产物,其余9个座位全都扩增出目的片段,其中2个座位(Po33和Po48)为单态,剩下7个座位表现出多态性,其多态座位比例为77.8%、平均杂合度为0.3856,明显低于自然和养殖群体。在具多态性的7个基因座位上均发生了基因一着丝点之间的重组,重组率在42.6—100%之间。结果显示通过抑制第二极体排出获得的牙鲆雌核发育群体在个体和群体水平尚具有一定的基因杂合。 3、利用20对微卫星引物对人工诱导的具有同一亲本的牙鲆异质和同质雌核更多还原

【Abstract】 Population genetics of the left-eyed flounder, Paralichthys olivaceus (T. & S.), including natural and cultured slocks of Shandong coastal waters of China was assessed using microsatellite markers. The genetic variations and the recombination rates between microsatellite markers and the centromere of meiogynogenetic offspring were also analyzed. In the meantime, a microsatellite-centromere mapping was constructed with the data depriving from the meiogynogenesis and mitogynogenesis stocks. The linkage relationship between microsatellite loci can be obtained from the mitogynogenesis stock. The main results shown as follows:1. The genetic variations of the natural and cultured stocks of Paralichthys olivaceus were assessed at 10 microsatellite loci (Pol, Po13, Po33, Po35, Po42, Po48, Po56, Po89, Po91, Po-strl). All loci are polymorphism. The average number alleles of per locus were 6.7 and 6.1, and the number of effective alleles (ae) of each locus in the natural and cultured stocks was 1.8-6.8 and 2.5-6.7, respectively, and The value of average heterozygosity (H) were 0.8120 and 0.7310. Genetic similarity (I), genetic distance (D) and coefficient of gene differentiation (Gst) between these two stocks were 0.8558, 0.1557 and 0.0558, respectively.The value of polymorphism information content (PIC) , power of discrimination (DP) and probability of paternity exclusion (PPE) were 0.59-0.84,0.54-0.86 and 0.41-0.72 at the 10 loci of the natural stock, respectively. The results indicated that the 10 microsatellite loci to be selected were very sensitive and could be used in the parentage and kinship determination of the artificial gynogenetic stock of left-eyed flounders and further genetic breeding study.2. Ten above polymorphism microsatellite markers were used to detect the genetic variations of the meiogynogenesis stock. There was no amplified product atPo91 locus because of the existence of null allele. Two loci (Po33 and Po48) were monomorphic and the rest were polymorphic in this stock. The mean proportion of polymorphic loci and the average heterozygosity were 77.8% and 0.3856, respectively. Compared with results of population genetics study, the genetic variation level of meiogynogenesis stock was lower than those of the natural and cultured stocks.Recombination was observed at the 7 polymorphic loci and the recombination rates between microsatellite locus and centromere were 42.6—100%, respectively. The results indicated that there was higher heterozygosity in the first meiogynogenetic generation owing to crossover between the homologous chromosomes during the meiosis-1 .3. Among the 20 loci used in the study on genetical analysis of meiogygenesis and mitogynogenesis stocks. A microsatellite-centromere mapping was constructed using the data depriving from the meiogynogenesis stock. The genetic distance between kopl5, Po42, Pol and the centromere was 15.8cm, 28.9cM and 32.4cM, respectively. The distance between the rest loci and the centromere was nearly 50cM, respectively.The linkage relationship between microsatellite loci were from the mitogynogenetic offspring’s allele separation pattern. Po13 and Po56, Po91 and kop18, kop15 and kop21 are linkage.更多还原